Improvement in rotary pumps



vUNITED STATES LUKE CHAPMAN, 0F COLLINSVILLE, CONNECTICUT, ASSIGNOR OF ONE-HAL HIS RIGHT TO WILLIAM J. WOOD, OF SAME PLACE.

PATENT OEEIGE.

lMPRQvEMENT IN RoTARv PUMPS."

Specification forming part of Letters Patent No. 137,055, dated March 25, 1873.

and useful Improvements in Rotary Pumps,

which are as well applicable to rotary motors, meters, and blowers, of which the following is a specification, reference being had to the accompanying drawing, in which- Figure lis a top view of the complete pump. Fig. 2 is a view of the same in central horizontal section through the plane, indicated by the dotted lines :c .fr in Figs. 5 and 6. Fig. 3 is a top view of the interior mechanism of the pump, consisting of the duplicate rotary pistons and the valves with which they are equipped. Fig. 4 is an end view of the parts shown in Fig. 8. Fig. 5 is a view of the complete pump in vertical section through the plane, indicated by the dotted line x1 .rl in Fig. l. Fig. 6 is a view ofthe complete pump in vertical section through the plane indicated by the dotted line x2 x2 in Fig. 1.

The outer shell or case is composed of two duplicate parts. One oi' vthese duplicate parts is composed of the two hollow intersecting cylinders a andl b, and the other of the two duplicate parts is composed of the two hollow intersecting cylindersa and b. The cylinders a and a' are duplicates, and the cylinders b and b are duplicates. The whole is, however, cast in one piece. The letter c indicates the ingress-pipe for the iiuid, and c the egresspipe. The pump has two duplicate rotating pistons, d and d1, hung on axes cl2 and d3, and made to rotate synchronously by means of the gears d4 d5. The piston d just fills the cylinder b', but there' is a water-space around it in the cylinder a. In similar manner the piston d1 just fllls the cylinder l, but there is la waterspace around it in the cylinder a. These two pistons rotate in the direction indicated'by the arrows in Fig. 4. Thepiston 0l has two round buckets or valves,j'f1, restingin appropri-ate valve-seatsfzlf3 in the piston, and always revolving with it. They just fill out to the shell. The piston d1 has corresponding valve-seats j'4 f5, which are temporarily lled by the'valvesfA-f1 as the two pistons rotate. The piston dlhas, in like manner, two cylindrical valves, g gl, fitting in suitable valveseats g2 g3. The piston d has corresponding valve-seats g4 g5, which are temporarily lled by the valves g g1 as the two pistons revolve. The valve-seatsf2f3 g2 g3 each take in more than half the valve that rests in it so as to,

keep the valves to the proper piston.

It will be seen that the arrangement described forms a double pump, so to speak.

I claim as my invention- The combination of the two duplicate parts a b and a b, and the two duplicate rotary pistons d d1, each equipped with one or more cylindrical va1ves,jfl q g1, and each having a valve seat or seats for the reception of the valve or valves carried by the other piston, the whole constructed and designed to operate substantially as described.

LUKE CHAPMAN. Witnesses:

OLIVER F. PERRY. ALBERT L. THAYER. 

